Method of securing valve stems to heads



.my 21, 1925.v 546,358

P. E. ATWATR METHOD OF SECURING VALVE STEMS TO HEADS Filed De-'.. l. 1924 Cit Patented July 21, 1925.

murenA STATES PAUL E. ATWATEP, OF TOLEDO, OHIO, ASSIGNOR T0 PATENT OFFICE.-

THE TOLEDO STEEL :PRODUCTS COMPANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO.

METHOD OF SECURING VALVE STEMS TO HEADS.

Application filed December 1, 1924. erial No. 758,024.

To all 'ni/10m, it 'may concern:

Be it known that I, PAUL E. A'rWATnn, a citizen of the United States, andra resident of Toledo, in the county of Lucas and State of Ohio, have invented a newv and useful Method of Securing Valve Stemslto Heads, which invention is fully set forth in the following speciication. i

This invention relates to the manufacture of poppet-valves and the like, and particuinitial threaded connection therebetween.

It is found, however, with this and other methods ,heretofore .employed in. connection with the-welding of such parts, 'that an entirely satisfactory joint is not obtained, and the, object of the present invention is to so treat and intimately connect the parts before welding that a highly effective and du' rable weld is obtained, thereby increasing the practicability and commercial' value of such valves.

The invention is fully described in the following specification, and an illustration of one embodiment thereof and of the steps -in the method employed are illustrated in thel accompanying drawings, in wh1ch,-

Figure l designates the headof the valve stem in separated relation with the stem in the act of being insertedy through the head opening,r and with its head securing end roughened in accordance with the invention. Fig. 2 is a similar viewiwith the stein partly threaded through the -head and with the rougi-honed end of the stein in connection. Fig. 8 shows the roughened portion ot the stein in the act of being forced into the head opening with the hea'd, a portion ot the stem and the head supporting member in section, and Fig. 4 is an elevation oli the completed valve with the head end thereof in section to indicate the Weld between the par-ts.

Referringr to' the drawings, l designates the head of a valve ot the poppet type, and 2 the stem therefor.

ln carrying out the invention, the head is prmided with an opening 3 axially therer through adapted to freely fit the stein for sliding movements thereon and the stein end,

to which the head is to he welded, knurlcd or otherwise suitably fashioned or acted on to forni a roughened surface 4 entirely around thc tially equal ing'. v

,The roughened surface 4 'is preferably composed of a plurality of small projections formed', .in the present instance, by providing astem surface with a succession of circumferential and 'a successiono'f longitudinal cuts or recesses, the .forming of which forces the metalout so that said projections extend beyond the normal surface of the stem and render 'the roughened surface slightly larger in diameter' than the stem body and the head opening 3. .This differ ence in diameter of the stem surface 4 of stein and ot a length substanto the length of the head openthe head opening requires the application of pressure to force one within the other and to effect the necessary reduction insize of the roughened surface to accommodate itself to the opening. The 'Force required for this purpose causes the projections to be reduced in size and to dig into the wall of the head opening, .thereby providing` a quite rigid intimate connection between the head and stern which materially facilitates welding' and the terminey of a strong, durable and integral union between the parts, for it is found that the more intimate the connection between the parts before weldingr the more perfect is the weld. The welded union, which is thus effected between the parts, is superior to the union effected between joints of threaded or other forni heretofore used preparatory to the welding,r operation. Fig. 3 illustrates a torce applying means of which 5 is the head support and G a plunger for forcing the stern into the head.

lt is evident that the method employed consists in providing the stem with a rou 1h- .encd surface. havingy a plurality ot projections and beingr ot slightly greater dialnetcr than the. head opening. tori-iner the roughcned portion of the stem into thehcad opening to efl'ect an intimate engagement'of the projections of" roughcned surface with thc wall of vthe head openingr and then electrically weldingr the joint between the head l and stein thus formed.

I wish it understood that niy invention is not limited lto any specific construction, arrangement or torni of the parts` or to the particular method described', as it is capable 1 of numerous modifications and changes withouftdeparting from .the spiilitofuthe claims.

y Havingw -thvus described my invention what I claim as Anew and desire to secure by Letters Patent is:

' :1. The method of'securmglvglve'heedsand lStems together, consisting in proifiding the, 'stem with e'roughened portion of slightly' greater diameter -than the head opening, oroing'the roughened-portion of the stem finto 'the head opening by axial pressure to effect an intimate joint between the two; and

electrically weldingl the'v joint thus formed.:

and stems together, consisting in providing the stementirelyaround an end portion thereof lwith a. surface of knurled form which kis of'slig'htly greater diameter than the head openlng, inserting the stem thi-'u the head u and applying axial pressure thereto to vforce vthe knurled portion of the stem into the head opening to cause the knurled surface projectionsto dig into the wall of the head opening and form a substantially rigidjntimate connection therebetween, and then Aeleo-` trically Welding the joint thus formed.

In testimonywvhereof, ,I 'have hereunto subscribed'my neme to this specification. 

